Firebase Auth - only errors returned from signInWithEmailAndPassword as success hangs

[meavydev]

This is running on a Kobweb API call under JVM, so there could be some different initialisation in there.

Stepping through the code, it appears that the enqueueRefreshTokenCall is hanging on this line:

                             [email protected] = user

It goes through the successful response and then sets up the refresh token call...

            override fun onResponse(call: Call, response: Response) {
                if (!response.isSuccessful) {
                    source.setException(
                        createAuthInvalidUserException("verifyPassword", request, response)
                    )
                } else {
                    val body = response.body()!!.use { it.string() }
                    val user = FirebaseUserImpl(app, jsonParser.parseToJsonElement(body).jsonObject)
                    refreshToken(user, source) { AuthResult { it } }
                }
            }

Which calls the enqueueRefreshTokenCall...

    internal fun <T> refreshToken(user: FirebaseUserImpl, source: TaskCompletionSource<T>, map: (user: FirebaseUserImpl) -> T?) {
        refreshSource = refreshSource
            .takeUnless { it.task.isComplete }
            ?: enqueueRefreshTokenCall(user)
        refreshSource.task.addOnSuccessListener { source.setResult(map(it)) }
        refreshSource.task.addOnFailureListener { source.setException(it) }
    }

Which gets back a successful response with the token, but the [email protected] = user line never completes, so the source.setResult call never occurs. Hence the hang.

            @Throws(IOException::class)
            override fun onResponse(call: Call, response: Response) {
                val body = response.body()?.use { it.string() }
                if (!response.isSuccessful) {
                    signOutAndThrowInvalidUserException(body.orEmpty(), "token API returned an error: $body")
                } else {
                    jsonParser.parseToJsonElement(body!!).jsonObject.apply {
                        val user = FirebaseUserImpl(app, this, user.isAnonymous)
                        if (user.claims["aud"] != app.options.projectId) {
                            signOutAndThrowInvalidUserException(
                                user.claims.toString(),
                                "Project ID's do not match ${user.claims["aud"]} != ${app.options.projectId}"
                            )
                        } else {
                            [email protected] = user
                            source.setResult(user)
                        }
                    }
                }
            }

My Kobweb code is actually using firebase-kotlin-sdk 2.1.0 and the latest Kobweb with Kotlin 2.

[meavydev]

Actually I just realised there is code behind the FirebaseAuth.user assignment and the problem is that it uses:

                GlobalScope.launch(Dispatchers.Main) {

Which is obviously a bad thing to do, as GlobalScope is one of the things that they say never to use... plus the documentation on Dispatchers.Main for JVM says Android / Swing / JavaFX, so I'm guessing there is no implementation that would work on the Kobweb API backend JVM.

On Kobweb this just hangs and none of the code in this section runs:

                GlobalScope.launch(Dispatchers.Main) {
                    if (prev?.uid != value?.uid) {
                        authStateListeners.forEach { l -> l.onAuthStateChanged(this@FirebaseAuth) }
                    }

                    if (prev?.idToken != value?.idToken) {
                        val result = InternalTokenResult(value?.idToken)
                        for (listener in internalIdTokenListeners) {
                            Log.i("FirebaseAuth", "Calling onIdTokenChanged for ${value?.uid} on listener $listener")
                            listener.onIdTokenChanged(result)
                        }
                        for (listener in idTokenListeners) {
                            listener.onIdTokenChanged(this@FirebaseAuth)
                        }
                    }
                }

[meavydev]

Actually as a quick hack I have taken a local copy of firebase-java-sdk and removed all the Dispatchers.Main in FirebaseAuth.kt and this has got me further.
So I really think you need to reasses the use of GlobalScope.launch(Dispatchers.Main) and replace them with something that is more cross platform friendly.